In recent years, music contents and so on have been distributed to an indefinite number of network terminal devices (computers) from a Web site via a network such as the Internet.
A computer user is able to record the distributed music contents on a wide variety of recording media in a state of digital data, so as to generate a music soft of favorite music that is recorded with a satisfactory tone quality, as the user wishes.
In this way, a computer user has accessed a Web site and recorded music contents on a recording medium freely. However, the act of distributing music contents by the person who set up the Web site without permission of the copyrighter, who is the owner of the music contents, will cause a problem of an infringement of the copyright of the music contents.